I. FIELD OF THE INVENTION
This invention relates generally to a machine for laying rolls of sod, and more particularly, to a sod laying machine which can be operated by a single person to unroll sod in a forward or reverse direction.
II. DISCUSSION OF THE PRIOR ART
Laying rolls of sod to produce a lawn is a labor intensive, time consuming yet delicate procedure. Rolls of sod harvested from sod farms are typically very heavy due to the thin layer of earth attached to the roots of the grass. Further, the tensile strength of the sod roll varies from one sod roll to the next due to the moisture content, the thickness of the grass, the age of the grass, and the variety of grass. Consequently, the difficulties in laying rolls of sod due to their weight an varying tensile strength usually requires one to unroll the sod by hand. Further complicating the unrolling procedure is ensuring that the sod roll is unrolled properly to avoid unsightly buckles. Due to different landscaping designs, sod occasionally needs to be rolled out in limited spaces and in areas having restricted accessibility. For instance, structure walls, retaining walls, fences, trees and gardens make the job of laying sod difficult and tedious. Further, the terrain of the land also varies due to hills and uneven grades. Thus, numerous difficulties and obstacles can be encountered when laying rolls of sod.
Various machines have been designed to reduce the labor involved in unrolling layers of sod, and to reduce the time involved. However, most machines suffer from one or more limitations such as limited maneuverability, they have high center of gravities and tip easily on uneven grades including hills, and they can only unroll sod in one direction. Further, they are often complicated and expensive. Finally, they can be difficult to use and require extensive time and patience in adapting a roll of sod to the machine for subsequent unrolling.
U.S. Pat. Nos. 4,890,801, 4,878,542, and 4,754,815 to Brouwer et al teach a sod laying machine. This machine has a front and rear sections articulated together wherein a forward boom includes a drive mechanism for dispensing sod rearwardly and beneath the wheels of the machine. The machine includes a pair of outriggers to prevent tipping of the machine. This machine has a high center of gravity thus requiring significantly long outriggers. Further, this machine can only unroll sod in one direction, namely, rearwardly. Thus, in restricted areas, this machine may not be suitable for a sod laying application requiring the roll sod be unrolled in the forward direction.
U.S. Pat. No. 3,982,711 to Bradley et al describes a sod laying machine which is rather complicated and cumbersome to use. This machine necessitates that individual sod rolls are passed between closely spaced endless drive belts in order to preserve the integrity of the roll. This machines takes up a considerable amount of space, is difficult to maneuver, and can only dispense rolls of sod in one direction. Further, it is adapted to be pulled by a tractor and is not adapted to be used or steered by an individual.
Thus, a sod laying machine which can lay rolls of sod in either the forward or a rear direction, which is easily maneuverable, and not subject to tipping on hills is very desirable. Further, a machine which can unroll large rolls of sod to reduce the total number of sod rolls required and to reduce the number of gaps between rolls of sod is desirable as well. Finally, an inexpensive, easy to use machine which is adapted to be operated by a single person is desirable as well.